1. Field of the Invention
The present invention relates to a reflector, to a method of manufacturing the same, and to a display device using the reflector. More particularly, the present invention relates to a reflector having excellent directivity of reflected light which can provide increased intensity of the reflected light in a display device, such as a liquid crystal display device and so forth, and to a display device using the reflector.
2. Description of the Related Art
Display devices, such as liquid crystal display devices, include reflective display devices in which a reflecting surface is provided on the back of a display cell, semi-reflective display devices in which a semi-transmissive reflecting surface is provided on the back of the display cell and a backlight is further provided on the back thereof, and backlight-type display devices in which a backlight is provided behind the display cell. The above backlight is composed of a light guide element, a reflecting surface formed on the back of the light guide element, and a light source for providing light into the light guide element.
Hitherto, a flat mirror surface including a metal film, such as aluminum, deposited thereon, or a rough surface having the metal film deposited thereon has been employed as the reflecting surface.
When the reflecting surface is a flat mirror surface, light cannot be scattered at the reflecting surface, so that it is difficult to impart a sufficient display luminance to the display cell.
When the reflecting surface is a rough surface having the metal film deposited thereon, light can be scattered at the reflecting surface. However, the light scatters at the rough surface in random directions, while the effective viewing angle of a display cell, such as a liquid crystal cell, is limited to a fixed angle, so that the luminance of the reflected light cannot be effectively increased within the range of the effective viewing angle.
In order to allow the reflected light to have a directivity within the angle range in which the luminance of the reflected light increases, it is necessary to optically design the reflecting surface. In addition, it is necessary to form optically designed fine irregularities on the optical reflecting surface. In the conventional reflecting surface, however, it is difficult to form an optical surface having fine irregularities with high accuracy, and to manufacture the optical surface in large quantities.